Indicating and control device



Oct. 9, 1956 R. B. BLAND 2,766,445

INDICATING AND CONTROL DEVICE Filed Nov. 23, 1953 5 Sheets-Sheet l'khwaezas pd INVENTOR. fiia/A/pAo 5 5444/0 Oct. 9, 1956 R. B. BLAND2,766,445

INDICATING AND CONTROL DEVICE Filed NOV. 23, 1953 5 Sheets-Sheet 2INVENTOR.

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Oct. 9, 1956 R. B. BLAND 2,766,445

INDICATING AND CONTROL DEVICE Filed Nov. :23 195:5 5 Sheefi-Sheet 4 R.B. BLAND Oct. 9, 1956 INDICATING AND CONTROL DEVICE 5 Sheets-Sheet 5Filed Nov. 23, 1953 United States Patent 9 INDICATING' AND CONTROLDEVICE Reginald B. Bland, Los Angeles, Calif. Application November 23,1953, Serial No. 393,591 9 Claims. (Cl. 340345) The present inventionrelates to improved means and techniques useful in various systemswherein it is desired to represent, either locally or remotely, theposition of an element moved either manually or autometrically. v

As will be gleaned from the following description, the present inventionis universally applicable in systems wherein it is desired to produceindications in either analogue or digital form with respect to movementsof an element such as, for example, the movable element of a pressuregauge, range finder or other operating means.

The present invention contemplates the provision of improved meanswhereby, for example, the angular position of a shaft may be indicatedeither locally or remotely in terms of numbers, the numbers being usedeither for indication purposes or for printing, as desired.

Another object of the present invention is to provide an improvedfollow-up system in which the position of a remotely controlled elementis truly representative of the position of an actuated member withoutthe possibility of loss of synchronism between such element and member,as is possible in systems incorporating Selsyn drives.

Another object of the present invention is to provide an arrangement ofthis character which involves rotary means for producing indications interms of the angular position of a rotary shaft without the necessity ofa commutator.

Another object of the present invention is to provide an arrangement ofthis character employing leading and trailing brushes so as to obtain amore uniform output signal.

Another object of the present invention is to provide an arrangement ofthis character in which brushes are movable into engagement withconducting segments on a matrix plate to obtain a reading or indication,with associated means for automatically interrupting the current flowingbetween such brushes and such conducting segments prior to disengagementofsuch brushes from such segments to thereby assure long contact life.

Another object of the present invention is to provide an arrangement ofthis character involving a brush and conducting segments on a matrixplate, with means for moving such brush into engagement with theconducting segments only when a reading or indication is desired.

Another object of the present invention is to provide an arrangement ofthis character involving a rotary element which requires the applicationof a relatively small amount of torque, only that necessary to overcomebearing friction, to position that element for obtaining readings orindications in terms of its angular position.-

Another object of the present invention is to provide an improvedarrangement of this character incorporating a matrix plate which hasconducting segments thereon ice to produce indications of the in termsof coded decimals.

Another object of the present invention is to provide an improvedarrangement of the character indicated above, characterized by itssimplicity and inexpensiveness.

The features of the present invention which are believed to be novel areset forth with particularity in the appended claims. This inventionitself, both as to its organization and manner of operation, togetherwith further objects and advantages thereof, may be best understood byreference to the following description taken in connection with theaccompanying drawings in which:

Figure l is a longitudinal sectional view through a converter embodyingfeatures of the present invention.

Figure 2 is a view taken in the direction indicated by the line 2-2 inFigure 1.

Figures 3, 4, 5 and 6 are sectional views taken along correspondinglines 3-3, 44, 55 and 6-6 in Figure 2.

Figure 7 is a view taken in the direction indicated by the line 77 inFigure I.

Figure 8 shows, partly in structural and partly in schematic form, anindicating system embodying features of the present invention in whichthe converter illustrated in Figure 1 is electrically connected.

Figure 9 shows, in simplified form, a portion of a system illustrated inFigure 8 for purposes of explaining the manner in which the units, tensand hundreds brush pins are normally aligned and the manner in which thetens and hundreds brush pins are effectively shifted backwar'dly, usinga leading and trailing brush pin arrangement, at the time the digit 7, 8or 9 is indicated so as to assure accurate indications in the tens andhundreds colurnns at all times.

In the following description of the invention, the mechanical featuresof the converter illustrated in Figures 1-7 are first described and thenthe manner in which such converter is connected electrically isdescribed in connection with Figure 8.

position of a rotary shaft Description of converter illustrated inFigures 1-7 The converter incorporates a housing 1 comprising the twocasing halves lA and 1B in which the rotary shaft 2 is journaled. Oneend of such shaft 2 is adapted to be connected to a trailing device suchas, for example, a range finder, a pressure gauge and the like, althoughas illustrated herein, a manually operated knob 3 is afiixed to suchshaft 2 to produce the desired rotation of the shaft 2.

The complementary casing halves 1A and 1B have mounted therein ballbearing structures 5 and 6, respectively, with inner and outer racemembers. The shaft 2 extends through the aligned inner-race ways and theshaft 2 is provided with shoulders which abut the correspondinginner-race ways of the bearings 5 and 6. The bearing 6 is maintained inadjacent position by the plug 7 threaded in the hub of the casing half1B, such plug being locked in adjusted position by the set screw 8threaded in the hub. The outer race member of the bearing 6 is snuglyreceived within an annular bore in the casing half 13.

The outer race of the bearing 5 is likewise snugly re ceived within thecollar 9 which is recessed Within an annular flange of the casing half1A.

A matrix plate or disk 70 with conducting segments thereon, asillustrated in Figure 7, is mounted on the shaft 2 for movement in theaxial direction of the shaft but is prevented from rotating with theshaft, using the structure now described.

The matrix plate 70 is recessed in the flanged disk 72 serving as abacking plate. The matrix plate 70 and a disk 72 are secured together asa unit by three recessed machine screws 73 (Figures 1 and 7) which arethreaded in cylindrical guide pins 75. Such guide pins 75 are slidablein slightly oversized bores 76 in the casing half 13 to provide guidedaxial movement of the matrix plate 70 and, of course, preventingrotation of the matrix plate. The matrix plate 70 and backing plate 72is moved by solenoid structure which includes the solenoid winding 80.For this purpose, the backing plate 72 is secured on the sleeve 82 whichis slidable on the shaft 2. One end of the sleeve 82 is provided with aretaining ring 84 serving as an abutment for one end of the prestressedcoil compression spring 85 which has its other end abutting against anannular solenoid coil form 87. The coil form 87, as shown, comprises aring having a U-shaped cross section and such ring is aflixed to thecasing half 13 by the locking screw 88. The coil spring 85 thus normallybiases the backing plate 72 and the attached matrix plate 70 to the leftin Figure l to a position as shown wherein the annular flange 82A of thesleeve 82 abuts the coil form 87.

a The sleeve 82 also mounts the annular magnetizable sleeve 90. Thismagnetizable sleeve 90 has one of its ends abutting a shoulder on thesleeve 82 and the other one of its ends retained by the retaining ring84. When current flows through the solenoid winding 80, the magnetizablesleeve 90 is moved to the right in Figure 1 to move the matrix plate '70axially so as to move conducting segments thereon into engagement withbrushes mounted on the disk 92. This disk 92 thus serves as a stopmember for movement imparted to the matrix plate 70 by the solenoid 88.

While the disk 92 is keyed to the shaft 2 for rotation therewith, it iscontemplated that, at the time the matrix plate 70 is moved intoengagement with the brushes on the disk 92, the shaft 2 and the disk 92are stationary.

In other words, it is contemplated that the solenoid 88 be energizedonly when the shaft 2 is stationary so as to derive information, usingmeans and techniques described hereinafter, useful in characterizing theparticular angular position of the shaft 2.

The matrix plate 70, as shown in Figure 7, comprises a central apertureddisk upon one face of which is disposed conducting portions. Theseconducting portions are represented in black in Figure 7 and compriseconducting rings and segments, certain segments being in conductiverelationship to corresponding conducting rings.

The conducting rings and segments on the matrix plate may be appliedusing well known techniques, particularly those used in providingso-called printed electrical circuits.

Specifically, the conducting segments on the matrix plate 70 include afirst series of five concentric rings 101, 102, 103, 104 and 185; asecond series of five conducting rings 111, 112, 113, 114 and 115; apair of diametrically spaced arcs 4t) and 40A both having the sameradius; a pair of diametrically opposite arcs 41 and 41A each having thesame radius; a conducting art 42; a unit ring 10, a so-called tens leadring 11, a so-called tens trailing ring 12, a so-called one hundredslead ring 13, a so-called one hundreds trailing ring 14; with conductingsegments on the first series of circles 181-485 and with conductingsegments on the second series of circles 111115. These conductingcircles and conducting arcs are connected to different electrical leadsas represented by the small circles in Figure 7 so as to provideconnections shown in Figure 8. These leads are in the form of flexiblepigtails of wire of very small diameter, the leads being suflicientlyresilient to allow the above-described axial movement of the matrixplate 70. The first series of conducting rings 10l105 are termedso-called units rings and it is observed that the conducting segmentswhich extend radially from the rings are staggered circumferentially.The second series of circles l11115 are termed so-called tens rings andeach is connected electrically to spaced segments. The segments ondifierent rings are staggered circumferentially as shown.

The disk 92 carries brushes in the nature of spring biased pins forcontacting the various segments on rings 101105, and for contacting thearcs 40, 40A, 41, 41A and 42. The nature of these brushes is illustratedin detail in Figures 2-6.

It is observed that the pin brushes 101TL, 102TL, 103TL, 104TL and105TL, respectively, are positioned to engage the spaced segments on thecorresponding rings 1ti1-1ii5. Likewise, the so-called leading brushpins 111L115L, as well as the brush pins 111T115T are positioned toengage the spaced segments on the corresponding tens rings 111115.Similarly, the brush pins 401. and MT are positioned to contact eitherthe are 40 or 49A, such arcs being on the same circle. Also, the brushpins 41L and 41T are positioned to contact either segments 41 or 41A,such segments 41 and 41A having the same radius. Further, the brush pins42L and 42T are arranged to contact the segment 42. The brush pins 10TL,11L, 12T, 13L and 14T are arranged to contact, respectively, the contactrings 10, 11, 12, 13 and 14, all of which are maintained at the samepotential as described hereinafter.

It is thus observed that the various brush pins have the same referencenumeral as the corresponding conducting ring on the matrix plate '70 buteach brush pin is distinguished by a different letter, either T, L orTL. The letter L is used to denote a so-called leading brush pin, theletter T is used to designate a so-called training brush pin, and theletters TL used together signify both a trailing and leading function.Thus, in general, three series of brushes are provided, namely, a firstseries of brushes which are leading brushes, a second series of brusheswhich are trailing brushes and a third series of brushes which cooperatewith such leading and trailing brushes, depending upon which one isrendered effective.

Each of these brushes constitute pins of the type shown in Figures 3, 4and 6, extending through oversized bores in the insulated disk 92, suchpins being all biased in the direction of the matrix plate 70 bycantilever supported spring elements. Thus, as shown in Figure 2, thebrush pins 101TL-102TL and 18L are spring biased by corresponding springfingers each having their base integrally formed with a base portion 200which is secured by means of screws to the back side of the disk 92.

The brush pins 40T, 41T, 42T, 40L, 41L and 42L are spring biased in likemanner, as shown in Figure 4. The structure shown in Figure 4 forbiasing the brush pins 41L and 41T is typical not only of the structurefor biasing the other brush pins, including the brush pins 111L114L and111T115T, but also typifies the structure of the associated switches.Thus in Figure 4 the brush pin MT is urged upwardly by the cantileversupported spring element 205 having its base portion secured to the disk92. This spring element 205 extends to the left to form one contact ofthe normally open switch 41TS. The other element of such normally openswitch HTS is a cantilever supported spring element 209 which extendsrearwardly for engagement with the insulated pressure plate or disk 207which is operated as described later. The strip 'of insulating material208 is sandwiched between the elements 205 and 209. The spring elementor pin brush 41L is likewise a cantilever supported spring element whichis clamped at a point intermediate its ends to the disk 92 with aportion 211 thereof extending to constitute a movable element of thenormally closed switch 41LS, the other element of normally closed switch41LS constituting the stationary bar 210 secured to the plate 92. It isobserved that the various switches associated with the diiferent brushpins have the same reference numeral but have the letter S appendedthereto. Thus, the switch associated with the pin brush MT has thereference numeral 41TS and the switch associated with the pin brush 41Lhas the reference numeral 41LS.

The switches 48TS, 41TS, 42TS, 111TS, 112TS 113TS,

114TS and HSTS, as shown in Figure 8, are normally open switches. Theswitches 40LS, 41LS, 42LS, 111LS, 112LS, IIBLS, 114LS and HSLS arenormally closed switches. These series of normally open and normallyclosed switches having the reference letter S appended thereto, as willbe described later, are operated only when a special condition exists,namely, when the last digit or unit is either a 7, 8 or 9.

Physical means for actuating such switches is now described and includessolenoid operating means moving the normally spring biased insulatedpressure plate 207.

The pressure plate or disk 207 is aflixed as shown in Figure l, to anannular flange on the sleeve 215, such sleeve being slidably mounted onan annular hub of the casing half 1A. Such sleeve 215 carries an annularmagnetizable cylinder or armature 216 'which is disposed between ashoulder on the sleeve and the annular retaining ring 218.

The pressure plate 207 is biased to the right in Figure l by threeprestressed coil tension springs 220, each having one of its endsattached to the pressure plate 207 and the other one of its endsattached to the annular mounting plate 222 secured to the casing half1A. These springs 220 thus normally urge the flange on sleeve 215 incontact with the solenoid housing 225, which is secured to the casinghalf 1A. Such solenoid housing includes the elements 228, 229 and 230,all secured together as, for example, by brazing or soldering with, ofcourse, the solenoid coil 232 in place. The armature 216 is slidablymounted in the annular solenoid housing and moves to the left, when thewinding 232is energized, to move the pressure plate 207 to cause theaforementioned normally open and normally closed switches to be operatedas a unit. The motion of the armature 232 is limited by its engagementwith the solenoid housing element 229.

Thus, normally, with the solenoid windings 80 and 232 tie-energized, theelements assume the positions shown in Figure 1. When a reading isdesired, the solenoid winding 80 is energized to move the matrix plate70 in the axial direction of the shaft 2, whereby the conductingsegments on the matrix plate are brought into contact With the brushpins on the insulated disk 92. As will be described later, in the eventthat the reading contains a numeral 7, 8 or 9 in the so-called unitscolumn, the solenoid winding 232 is automatically energized to move thepressure plate 207 in the axial direction of the shaft 2 to cause theseries of normally open and normally closed switches on the back of theinsulated disk 92 to be operated.

Descrition of electrical circuitry illustrated in Figure 8 In Figure 8,the five outer contact rings 101--105 of the matrix plate 70, i. e., theso-called units rings, are connected, respectively, to one terminal ofthe indicating lamps 301, 302, 303, 304 and 305, respectively, the otherterminals of such indicating lamps being returned to the negativeterminal of voltage source 308 through corresponding resistances 301A,302A, 303A, 304A and 305A. Thus, the matrix plate and associated brushesare illustrated as controlling the energization of translating meanswhich is in the form of indicating lamps. t is noted that the terminalof resistance 305 is returned to the negative terminal of source 308 ina special manner to perform a blocking function as described in detaillater; namely, one terminal of resistance 305A being connected to oneterminal of lamp 305 and the other terminal of resistance 305A beingreturned through the relay winding 600 to the negative terminal ofsource 308. Thus, indicating lamps 301, 302, 303, 304 and 305 representrespectively, as qualified below, the units digit 0, 2, 4, 6 and 8,respectively. The 6 indicating lamp 306, also representing the numeral0, is connected in parallel with the other lamp 301, one terminal of thelamp 306 being connected to one terminal of lamp 301 and the otherterminal of lamp 306 being connected to the negative terminal of source308 through resistance 306A.

Illumination of single lamp 303, 302, 303, 30 i, 305 and 306 correspondsto the corresponding even digit, i. e., 0, 2, 4, 6, 8, 0. Illuminationof two adjacent lamps in the column serves as indication of the oddnumber that lies between the two even numbers. Thus, when the 0 and 2lamps 301 and 302 are energized simultaneously, the number 1 isindicated; likewise, when the lamps 302 and 303 are simultaneouslyenergized, the numeral 3 is indicated.

The lamps in the second column, namely, lamps 401, 402, 403, 404, 405and 406 represent the numerals ()0, 20, 40, 60, and 00, respectively.When one of such lamps 401406 is illuminated, the corresponding numeralis designated, and when two adjacent lamps are energized, the odd numbermultiplied by ten is indicated. Thus, for example, when the lamps 401and 402 are simultaneously illuminated, the numeral 10 is indicated, andwhen lamps 403 and 404 are simultaneously illuminated, the numeral 50 isindicated. The lamps 3-01, 402, 403, 404 and 405 each have one of theirterminals connected to a corresponding one of the matrix plateconducting rings 111, 112, 113, 13.4 and 115, the other terminals of thecorresponding lamps being returned to the negative terminal of source303 through resistances iiliA, 402A, 403A, 404A and 405A, respectively.The lamp has one of its terminals connected to one terminal of lamp 401and the other terminal of lamp 466 is connected to the negative terminalof source 408 through resistance 406A.

The lamps in the third column, namely, lamps 501, 502, 503, 504, and 506correspond, respectively, to the numerals 000, 260, 400, 600, 800 and000. These lamps when illuminated individually indicate thecorresponding numeral, but when two adjacent lamps are illuminated, thenumeral intermediate therebetween is indicated. Thus, when the lamps 501and 502 are simultaneously energized, the numeral is indicated, and whenthe lamps 502 and 503 are simultaneously illuminated, the number 300 isindicated.

The lamps 503, 502, 503, 504, and 505 each have one of their terminalsconnected to corresponding segments 40, 40A, 41A, 41 and 42, the otherterminals of such lamps being connected through correspondingresistances 501A, 502A, 503A, 504A and 505A to the negative terminal ofsource 303. Lamp 506 has one of its terminals connected to one terminalof lamp 501 and the other one of its terminals connected throughresistance 506A to the negative terminal of source 303. Since theconducting r'ings 10, 11, 12, 13 and 14 are continuous rings and aremaintained at the same potential, they are all represented by a singlecircle in Figure 8 for simplicity, such conducting rings being connectedto one terminal of the matrix solenoid winding 80, to one terminal ofthe so-called blocking solenoid winding 232 and to one terminal of themanually operated operating switch 310. The other terminal of the switch310 is connected to the positive terminal of source 308. The otherterminal of solenoid winding 30 is returned to the negative terminal ofsource 308 and the other terminal of the solenoid winding 232 isreturned through the relay switch 600A to the negative terminal ofsource 308. The Winding 600 of such relay for actuating the normallyopen switch 600A has one of its terminals connected to the negativeterminal of source 308 and the other one of its terminals connected toone terminal of resistance 305A so that whenever current flows throughthe indicating lamp 305, the same current flows also through the relaywinding 600 to cause operation of switch 608 for a blocking purpose.

Since the relay winding 600 is serially connected with the lamp 8 andsuch lamp 8 is used to indicate not only the unit 8 but also the unit 7and 9, the relay winding 600 is energized when either 7, 8 or 9 isindicated to cause the blocking solenoid 232 to be energized to in turncause operation of the series of normally open and series of 7 normallyclosed switches mounted on the back side of the brush plate 92.

Normally when a unit digit other than 7, 8 or 9 is indicated, theblocking solenoid winding 232 is not energized and the series ofso-called tens switches and hundreds switches are in the positionillustrated in Figure 8, in which case the leading brush pins 40L, 41Land 42L are interconnected with the leading tens brush pins 111L, 112L,1131s, lit-4L and 115L.

On the other hand, when the blocking solenoid 232 is energized, theseries of normally closed switches are opened and the series of normallyopen switches are closed to correspondingly disconnect the leadingbrushes and to interconnect the trailing hundreds brushes with thetrailing tens brushes.

It is observed that while Figure 8 shows additional brush pins 40AL,41AL, 41AT and iilAT interconnected by dotted lines to additionalswitches 40ALS, 41ALS, 41ATS and 40ATS, these additions shown in dottedlines are for purposes of explanation only and are of course notincluded in the actual structure shown in Figure 2, these additionalbrush pins and additional switches shown in dotted lines being addedsince there are corresponding contact segments 40, 40A, and 41, 41A.

Figure 9 illustrates in simplified form the manner in which the brushpins are aligned in the physical structure illustrated in Figures 1-7.For purposes of simplification, the digits segments, the tens arcs andthe hundreds arcs are shown staggered and the units brushes arerepresented by a composite conducting bar 501; the tens brushes by acomposite conducting bar 502; and the hundreds brushes by the conductingbar 503. Actually, the conducting bar 501 represents the brush pin and(101TL, 102TL, 103TL, 104TL or 105TL depending upon the particularposition of the rotatable shaft 2) as shown in Figure 9 actually theconducting bar 501 corresponds to the brush pins 10 and 103TL since thesegment corresponding to the digit 4 is contacted as shown in Figure 9.

Likewise, the conducting bar 502 in Figure 9 represents generally thebrush pins 11L and (111L, 112L, 113L, 1141. or ESL depending upon theangular position of the shaft 2), actually as shown in Figure 9 theconducting bar 502 represents, assuming the angular position of theshaft 2 as indicated, the brush pins 11L and the brush pins 111L and115L since the arcs corresponding to 80 and 00 are being contacted.

Similarly, the contact bar 503 represents generally the brush pins 13Land (1111,, 112L, 1131s, 114L or 115L depending upon the angularposition of the shaft 2) actually as represented in Figure 9, assumingthe angular position of the shaft 2 as indicated, the contact bar 503 insuch special case represents the brush pins 13L, 111L and 115Lsince thecontact segments 800 and 000 are contacted.

It is observed that the contact bars 501, 502 and 503 are aligned. It isalso observed that the contact bars 502 and 503, shown in full lines,correspond to leading brush pins while the corresponding trailing brushpins are represented by the contact bars 502A and 503A, respectively,illustrated in dotted lines. As shown in Figure 9, indication isproduced on the lamps 505, 506, 405, 406 and 303 indicating, by theirillumination, the numeral 9, 900 and 94, it being rememberedsimultaneous illumination of the lamps 405 and 406 represent the numeral70. Assuming that the shaft 2 has an angular position displaced a smallamount from that illustrated in Figure 9, i. e., the condition existswherein the contact bars 501, 502 and 503 are axially aligned along theline 510, then in such case the contact bar 501 engages the contactsegments 6 and 8 simultaneously; the contact bar 502 continues to engagethe contact segments 111 and 115; and the contact segments 4-0 and 41Aare still contacted by the contact bar 503. In such case, the lamps 505and 506 still indicate the numeral 900, the lamps 405 and 406 stillindicate the numeral 90, but the lamps 304 and 305 are illuminated toindicate the numeral 7. Apart from this new indication, the blockingsolenoid 232 is now energized since the relay winding 600 as describedabove is serially connected with the lamp 305 and energization of therelay winding 600 causes the relay switch 600A to be closed to produceenergization of the blocking solenoid 232. In such case, as describedabove, the series of normally closed switches corresponding to theleading brush pins and corresponding to the conducting bars 502 and 503are rendered inetfective, i. e., such normally closed switches areopened, and the normally open switches are closed, such normally openswitches being represented by the conducting bar 502A in the case of thetens brush pins and such normally open switches being represented by thecontact bar 503 in the case of the hundreds brush pins. Thus, when thecontact bar 501 engages a conducting segment on the conducting ring, i.e., a segment corresponding to the digit 8, the contact bars 502 and 503are effectively shifted rearwardly a relatively small distance whereinthe same hundreds and tens indications are produced. Thus, tens andhundreds readings are derived from the trailing brushes when the lastdigit in the column is either a 7, 8 or 9, i. e., so long as an 8contact segment is engaged.

Assuming a further positioning of the contact bar 501 in the positionindicated by the line 502 wherein the units contact 501 engages only asegment on the 0 contact ring 101, then in such case immediately whenand as such contact bar 501 leaves a conducting segment 105 and contactsan 0 contact segment 101 exclusively, then the relay winding 600 isde-energized to again allow the leading contact bars 502 and 503 to beeffective.

This expedient of deriving readings from leading and trailing brush pinsautomatically depending upon the position units brush pin assuresaccurate indications, particularly in the transitional zone wherein thedigit in the units column changes from a 9 to a 0. This expedient allowslarger tolerance in manufacturing the matrix plate since, without thisexpedient, precise alignment of the edges of the contact segments 105,and 41A along a line represented by the dotted line 415 must exist. Further, this expedient provides a compensating elfect for mechanicalmisalignment and play in the rotary structure and assures accuratereadings even though the apparatus is subjected to wear resulting fromprolonged use.

. While the particular embodiments of the present invention have beenshown and described, it will be obvious to those skilled in the art thatchanges and modifications may be made without departing from thisinvention in its broader aspects and, therefore, the aim in the appendedclaims is to cover all such changes and modifications as fall within thetrue spirit and scope of this invention.

I claim:

'1. A converter of the character described, comprising: a casting havingtwo complementary halves, a shaft journalled for rotation in each ofsaid casing halves, a matrix plate slidably mounted in one of saidcasing halves, said matrix plate having a plurality of conducting areasthereon with a predetermined pattern, said matrix plate being slidableon said one casing half in the axial direction of said shaft, anelectromagnetic structure mounted on said one casing halt" andincorporating a movable element attached to said matrix plate for'movingthe same axially in accordance with energization of said electromagneticstructure, a brush plate secured to said shaft, brush pins mounted onand extending forwardly through said brush plate and aligned with saidconducting segments for contacting the same, a plurality of switchesmounted on said brush plate and having actuating members extendingrearwardly from said brush plate, said switches being connected to saidbrush-pins, a switch actuating plate slidably mounted in the other oneof said casing halves, an electromagnetic structure mounted on saidother casing half and having a movable portion thereof attached to saidbrush actuating plate for moving the same in the axial direction of saidshaft, said switch actuating plate being adapted to contact said switchactuating members in accordance with energization of said secondelectromagnetic structure.

2. In combination with the arrangement set forth in claim 1, electricalcircuitry involving a source of current, a switch serially connectedwith said source and with said first electromagnetic structure, a relayhaving a winding and an associated relay switch, means effective toenergize said relay when one of said brush pins engages a predeterminedcontacting segment, and a serial circuit comprising said source, saidswitch, said second electromagnetic structure and said relay switch.

3. In an arrangement of the character described, a casing, a shaftrotatably mounted in said casing, a matrix plate with conducting areasthereon slidably mounted in said casing, a brush plate mounted on saidshaft, said brush plate carrying brushes, means for moving said matrixplate so as to place said conducting areas into engagement with saidbrushes, translating means operated in accordance with engagement ofsaid brushes with said conducting areas, and switching meanselectrically connected with said conducting areas and said brushes andoperated in accordance with the contact between said conducting areasand said brushes for rendering predetermined ones of said brushesineffective to operate said translating means.

4. In an arrangement of the character described, a casing, a shaftrotatably mounted in said casing, a matrix plate slidably mounted insaid casing for movement in the axial direction of said shaft, a brushplate mounted on said shaft and having brushes extending forwardlythereof for engagement with conducting areas on said matrix plate, meansfor moving said matrix plate into engagement with said brushes,switching means connected to said brushes and mounted on said brushplate and having actuating means extending rearwardly of said brushplate, and means mounted on said casing for operating said switchactuating means in accordance with engagement of predetermined ones ofsaid brushes with predetermined conducting areas on said plate.

5. In an arrangement of the character described, a casing, a shaftrotatably mounted in said casing, a matrix plate having conducting areasthereon, a brush plate having brushes mounted thereon engageable withsaid conducting areas said brushes extending forwardly of said platewith a first series of said brushes being displaced from a second seriesof said brushes, first switch means connected to said first series ofbrushes, second switch means connected to said second series of brushesand a common actuator for actuating said first and second series ofswitch means, translating means controlled by said first and said secondseries of brushes, and means controlling said common actuator inaccordance with engagement of brushes of said one series engagingpredetermined conducting areas of said plate for rendering said one andsaid second series of brushes alternatively effective to control saidtranslating means.

6. In an arrangement of the character described, a casing, a shaftrotatably supported in said casing, a matrix plate having conductingareas thereon and slidably mounted in said casing, a brush plate mountedon said shaft and having a first series and a second series of brushpins extending forwardly for engagement with said conducting areas,means for moving said matrix plate with the conducting areas thereon inengagement with said first and second series of brush pins, a firstseries of 10 switches mounted on said brush plate and connected to saidfirst series of brush pins, a second series of switches mounted on saidbrush plate and connected to said sec ond series of brush pins, meansfor actuating said first and second switch means jointly, translatingmeans controlled by said first and second series of brush pins, andmeans controlling said actuating means in accordance with engagement ofbrush means of said one series engaging predetermined conducting areasof said plate for rendering said one and said second series of brushpins alternatively effective to control said translating means.

7. In an arrangement of the character described, a casing, a matrixplate mounted in said casing, a shaft rotatably supported in saidcasing, a brush plate mounted on said shaft, said matrix plate having afirst series of conducting areas, said matrix plate having a secondseries of conducting areas, first brush pins mounted on said brush plateengageable with said first series of conducting areas, a pair of seriesof brushes on said brush plate engageable with said second series ofconducting areas, translating means, first switch means interconnectingsaid translating means with one of said pair of series of brushes,second switch means interconnecting said other one of said pair ofseries of brushes to said translating means, and means controlled bysaid first series of brushes for rendering said first and second switchmeans alternately effective to interconnect said one of said pair andthe other one of said pair of series of brush pins to said translatingmeans.

8. In an arrangement of the character described, a matrix plate having afirst series of conducting areas, said matrix plate having a secondseries of conducting areas, first brush means engageable with said firstseries of conducting areas, a second and a third series of brushes bothengageable with said second series of conducting areas, translatingmeans, first switch means interconnecting said second brush means withsaid translating means, second switch means interconnecting said thirdbrush means with said translating means, and means incorporating saidfirst brush means and said first series of conducting areas forrendering said first and second switch means alternately effective.

9. In an arrangement of the character described, a casing, a shaftrotatably mounted in said casing, a matrix plate slidably mounted insaid casing in the axial direction of said shaft, said matrix platehaving conducting areas thereon, a brush plate mounted on said shaft,said brush plate having brush pins extending forwardly thereof in thedirection of said conducting areas, means normally biasing said matrixplate out of engagement with said brush pins, electromagnetic meansoperatively connected to said matrix plate for moving the same with theconducting areas thereon in engagement with said brush pins, a first andsecond switch means mounted rearwardly of said brush plate and connectedto different brush pins, said switch means having actuating membersextending rearwardly of said brush plate, a plate slidably mounted insaid casing and engageable with the actuating members of said first andsecond switch means for operating the same jointly, means biasing thelast mentioned plate out of engagement with said switch actuatingmembers and electromagnetic means for moving said plate to actuate saidfirst and second switch means.

References Cited in the file of this patent UNITED STATES PATENTS2,659,066 Sayer Nov. 10, 1953

